# Key Takeaways - Risk on runway surfaces contaminated with standing water, slush, or wet snow - Can render an airplane partially or totally uncontrollable during landing roll - Grooved runways can help prevent hydroplaning > [!danger] If deceleration is not detected and hydroplaning is suspected... > Raise the nose and use aerodynamic drag to decelerate to a point where the brakes become effective # Details ## Dynamic Hydroplaning - Relatively high-speed phenomena - Wedge of water under tire creates pressure equal to weight of plane - Related to tire inflation pressure: `8.6 * sqrt(tire pressure PSI)` ## Reverted Rubber Hydroplaning - Called 'steam' hydroplaning - Tire skidding heats up rubber, which reverts to its uncured state and traps/delays water exit. Trapped water heats and becomes steam, keeping the tire of the runway - Can persist at slower speeds (20kts or less) ## Viscous Hydroplaning - Can occur as much slower speeds, but requires a smooth surface - Tire cannot penetrate the thin film of water, and slips like on ice # Additional Resources - [[AFH Ch9]] - [The Science of Aircraft Hydroplaning](https://pilotinstitute.com/aircraft-hydroplaning/) from [[Pilot Institute]] - [The 3 Types Of Hydroplaning, And How To Prevent Them](https://www.boldmethod.com/blog/lists/2025/05/three-types-of-aircraft-hydroplaning/) from [[Bold Method]] ***Definition*** :: A condition that exists when landing on a surface with standing water deeper than the tread depth of the tires. When the brakes are applied, there is a possibility that the brake will lock up and the tire will ride on the surface of the water, much like a water ski. When the tires are hydroplaning, directional control and braking action are virtually impossible. An effective anti-skid system can minimize the effects of hydroplaning. ***Source*** :: [[AFH Glossary]] #glossary #concept